Efficacy and safety of pregabalin in elderly people with generalised anxiety disorder

Abstract

Background: Pregabalin is a novel compound that has been shown to have efficacy in the treatment of generalised anxiety disorder and is licensed for the treatment of the disorder in the European Union. Aims: The current study was designed to evaluate the safety and efficacy of pregabalin, an α2δ-ligand, in the treatment of generalised anxiety disorder in people 65 years and older. Method: This was a double-blind, randomised (2:1), placebo-controlled, 8-week trial of pregabalin, in flexible doses of 150-600 mg/day, in the treatment of DSM-IV generalised anxiety disorder with a baseline Hamilton Rating Scale for Anxiety (HRSA) total score ≥20. The primary outcome was end-point (week 8 or last visit, with last observation carried forward (LOCF)) change in HRSA total score. Results: A total of 273 patients (women, 78%; mean age, 72 years (s.d.=6); mean baseline HRSA total score, 26 (s.d.=4.6)) were randomised and received study treatment. On the primary intent-to-treat LOCF analysis, pregabalin was associated with a 2-point greater reduction in HRSA total score than placebo (12.87 v. 10.7; P < 0.05). In a post hoc repeated measures mixed-effect model analysis, pregabalin was associated with significantly greater improvement than placebo in the HRSA total score from week 2 (-9.8 (s.d.=0.6) v. -7.2 (s.d.=0.8); P=0.0052) through week 8 (-14.4 (s.d.=0.6) v. -11.6 (s.d.=0.8); P=0.0070). Significant improvement was observed in the pregabalin group on both the HRSA psychic and somatic anxiety factors. There was a significantly greater decrease from baseline in mean Hamilton Rating Scale for Depression (HRSD) score with pregabalin compared with placebo (-5.48 (s.d.=0.46) v. -4.02 (s.d.=0.59); P=0.041). Pregabalin was well-tolerated, with almost all adverse events in the mild-to-moderate range, and self-limiting (median duration of 4-16 days). Discontinuations due to adverse events were similar for pregabalin (10.7%) and placebo (9.4%). Conclusions: Pregabalin, in doses of 150-600 mg/day, was a safe and effective treatment of generalised anxiety disorder in patients 65 years and older. The anxiolytic efficacy of pregabalin had an early onset (by 2 weeks) and significantly improved both psychic and somatic symptoms of anxiety.